Electric latch for elevator-doors.



No. 687,775. Patented Dec. 3, |9OI.' N. P. OTIS &. A. SUNDT. ELECTRIC LATCH FOR ELEVATOR DOORS.

. (Application filed Aug. 14, 1900.) (No Model.)

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No. 687,775. Patented Dec. 3, IQOI.

' H. P. OTIS 8|, A. SUNDT.. I

ELECTRIG LATCH FOR ELEVATOR DOORS.

(Applicatipn filed Aug. 14, 1900.) (No Model.) 3 Sheets-Sheet 2.

I VIIIIIIIIIIIIIJIMIIIIKI II/Ill No. 687,775. Patented Dec. 3, 190i.

" N. P.,0TlS & A. SUNDT.

ELECTRIC LATCH FOR ELEVATOR DOORS.

(Application filed Aug. 14, 1900.)

(No Mqdel.) 3 Sheets-Sheet 3.

VUNITED STATES PATENT NORTON P. OTIS, OF YONKERS, AND AUGUST SUNDT, OF NElV YORK, N. Y., ASSIGNORS TO THE OTIS ELEVATOR COMPANY, OF EAST ORANGE, NElV JERSEY, A CORPORATION OF NEW JERSEY.

ELECTRIC LATCH FOR ELEVATOR-DOORS.

SPECIFICATION forming part of Letters Patent No. 687,775, dated December 3, 1901.

Application filed August 14, 1900. Serial No. 26,864. (No model.)

To all whom it may concern.-

Be it known that we, NoRroN P. OTIS, residing at Yonkers, in the county of Westchester, and AUGUST SUNDT, residing in the city and county of New York, State of New York, citizens of the United States, have in-. vented certain new and useful Improvements in Electric Latches for Elevator-Doors, of which the following is a specification.

IO In connection with certain building constructions and certain classes of apparatus, as elevators, it has become necessary to provide that the position of doors shall control other parts or devices or apparatus and to ef- I 5 feet this control through the medium of electrical energy transmitted by circuits made or broken by shifting the doors. l-Ieretofore the means used in this connection have not operated with the accuracy and certainty desired; and the object of our invention is to insure that the current cannot be completed until the door is not only closed, but latched, or only when the latch or bolt is in complete locking position, and so that the current will be broken not only when the door is unlatched, but even on a slight movement of the latch or bolt and before it is released from the keeper.

In the accompanying drawings, Figure 1 is a diagrammatic view illustrative of a conventional elevator system in which a motor-controlling circuit passes through switches on the elevator-doors. Fig. 2 isa sectional view Show ing the lock and keeper of one form of lock- 3; ing devicewith our improvements. Fig. 3 is a sectionalplan on the line 3 3, Fig. 2. Fig. 4is a section on the line t 4, showing the means for operating the detent of the keepercasing. Fig. 5 is a View looking in the direction of the arrow, Fig. 4..

Referring to the drawings, K represents a motor, shown as a shunt-wound electric motor, having an armature 70, connected in any suitable manner to operate a car L. The motor K is supplied with electric energy from a source M, shown as a battery, the poles of which are indicated by and the circuit 15 from the battery including the motor and also a controlling-switch N for making and 5c breaking the motor-circuit. A shunt-circuit from the motor-circuit, comprising conductors 16, 17, and 18, extends to the several landings Y Y Y, passing through door-switches 1 y if, operated by the doors g and through push-buttons 2 2'5 at the landings, and also including a suitable solenoid O for controlling the operation of the motor-controlling switch N. The door-switches are here shown conventionally, our particular improvements therein being hereinafter fully described. One of the contacts t of the switch N is carried by a pivoted armature 2., adapted to be attracted when the solenoid O is energized and close switch N, thus operating the elevator-motor, a suitable spring 25 retracting the armature and breaking the motor circuit when the solenoid is deenergized. The controlling-circuit, including the push-buttons z zz is adapted to be closed by the operation of any push-button, provided all the welldoors g are closed, completing the circuit through conductor 16. Then upon pressing any pushbutton, as z, and keeping the finger on that button it is evident that a circuit will be completed, including battery M and solenoid O, which solenoid will attract armature t and close the normally open switch N, thus starting the motor.

In electric elevator systems of the type herein briefly described as embodying our improved electric door-latch some means are ordinarily provided for automatically breaking the controlling-circuit and stopping the motor when the car has reached the desired landing; but this being no part of our invention and not necessary to an understanding thereof a complete system, including reversing means for the motor, has not been shown. The operatorat landing push-button z, in this instance, need only remove his finger from 0 the button when desired and the motor-circuit will be broken. It is clear that unless all the elevator-well doors are closed the controlling-circuit cannot be completed, and, as stated,ourinvention consists,primarily,inthe 5 construction of an electrical door latch or look whose function in an elevator system is substantially the same as that of thedoorswitches y 3 g above described.

Referring now more particularly to the con- :00

struction and operation of the door-lock, the lock-case A is secured to the door, which may be either a sliding or hinged door, the latch or bolt B being of any suitable character and engaging or entering the socket of the keepercasing 0, which is secured to the frame or to the other leaf of a two-part door. In the construction shown in Figs. 2 to 5 there is a latch B, with a hooked end adapted to enter the socket X and engage the shoulder y of the keeper. Thislatch is pivoted to the lock-case at the rear end and is vibrated by a cam 1 upon the knob-spindle 2 and depressed by a spring 3. The head or end of the latch carries a bridge D, of metal, insulated from the other part of the latch by insulating material 4, and within the keeper-casing are two pivoted arms E F on pivots insulated from the case, but connected by flexible connections 5 with binding-posts 6, so as to constitute electrical terminals. At the front of the keepercasing below the socket X is a beveled projection 7, adapted to be engaged by the beveled face of the latch-head, which is therefore lifted as the latch is carried toward the keeper, and springs 8 throw the arms E F outward to insure their engagement with the bridge D when the latch isin locking engagement with its keeper.

It will be seen that one of the arms or terminals E F is longer than the other and that the contact of the bridge and the shorter arm E will not take place until the head of the latch is not only in the keeper-casing, but pressed down in engagement with the keeper. As a result the lifting of the latch, even to an extent insufficient to disengage it from its keeper, will yet break the contact with the terminal E, and thus break the circuit, so that the apparatus or parts controlled by the electric current cannot be put into operation except only when the latch and keeper are in complete engagement.

In the elevator apparatus it is desirable to maintain each landing-door locked until the door or passage of the car or cage is opposite the said landing-door. \Ve secure this result by means of a detent G, which normally takes such a position in respect to the latch or bolt when the latter engages the keeper that the latch cannot be released until the shifting of the detent,resulting only when the cage is in proper position. As shown, the detent is a cross-bolt sliding transversely of the keeper-case above the position occupied by the latch when in position to engage the keeper and connected to a lever H, pivoted inside the door-frame at 9, thrown out by a spring 12, and with a roller 10 at the lower end in position to make contact with the cage or a projection thereof. When this occurs, and only then, the lever II will be pressed inward by the cage and the detent G is drawn back from the lock-case and the latch maybe lifted to open the landing-door. The under side of the detent G is inclined, so that it will tend to depress the latch when pushed inward.

Vhile we have shown a lock having a latch, we do so only as illustrating one form of locking means, having in mind the use of bolts and catches and any kind of device for engaging the keeper of the frame or other doorleaf, as in various forms of sliding and hinged doors, so that under the term latch as used herein we include any form of latch bolt or catch self-latching or requiring to be moved by hand into engagement.

lVithout limiting ourselves to the precise construction and arrangement of parts shown, we claim as our invention- 1. The combination in a door-fastening, of a latch or bolt and a keeper and electrical terminals controlled by a contact-piece carried by the bolt and arranged to complete a circuit only when the bolt is in completed locking relation to the keeper, substantially as set forth.

2. The combination of a door provided with a latch, a keeper for engaging the latch, electric terminals and a contact-piece carried by the latch, all arranged to permit such contact, and the completion of a circuit only when the latch is in engagement with the keeper, substantially as set forth.

3. The combination with a door, its latch and keeper therefor, of electric terminals and a contact-piece carried by the latch arranged to engage the terminals as the door is closed, and to be disconnected as the latch is moved prior to disconnecting it from the keeper, substantially as set forth.

4. The combination of a latch, a keeper and electric terminals and a contact-piece for completing a circuit by the contact of the contact-piece and terminals, and a detent whereby the said contact is maintained when the door is closed, and means for shifting the position of the detent, substantially as set forth.

5. The combination of the cage and landing-door of an elevator, a latch, a keeper and electric terminals and a contact-piece for completing a circuit by the contact of the contactpiece and terminals, and a detent whereby the said contact is maintained when the door is closed, and means for shifting the position of the detent when the cage is opposite the door, substantially as set forth.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

NORTON P. OTIS. AUGUST SUNDT.

Witnesses:

HARRY W. BARKLEY, H. R. MABSDEN. 

